1. Field of the Invention
The present invention relates generally to a method of operating a zinc-halogen secondary battery and more specifically to a method of operating the battery by which it is possible to effectively inhibit zinc dendrite from being formed on a negative electrode thereof in recharging the battery.
2. Description of the Prior Art
In the zinc-halogen secondary battery, the growth of zinc dendrite on the negative electrode has well been known as a serious probelem. This is because, once zinc is electrodeposited on the surface of the negative electrode in dendrite fashion in recharging the battery after the battery has been discharged, the cyclic lifetime of the battery is markedly reduced. In more detail, after the battery has been discharged, porous oxide such as ZnOx, Zn(OH)x is readily produced on the residual zinc layer on the negative electrode. Once these porous zinc oxide is formed theron, the electrodeposited zinc grows into coarse zinc crystal of less adhesion when the battery is being recharged, and finally dendrite is produced on the negative electrode. In the case where zinc dendrite is formed on the electrode, it is impossible to effectively form a uniformly thich electrodeposited zinc layer on the negative electrode, so that the cyclic battery lifetime is markedly reduced.
To overcome these problems, so far various zinc dendrite inhibitors have been developed to prevent zinc dendrite from being formed on the negative electrode or to improve the cyclic lifetime of the battery. However, these zinc dendrite inhibitors are not yet satisfactory.